Conventionally, there are portable terminal devices that execute control to make received voices easy to hear. For example, there is a technology with which multiple single-tone frequency signals are reproduced for a user to calculate the minimum hearing level based on the user's hearing result for processing a voice (Patent document 1).
Also, there is a technology with which if an operation signal is output that indicates a request for repetition of a guiding voice within a certain amount of time since the guiding voice has been output, the guiding voice is output again after adjusting a setting value designating output mode of the guiding voice (Patent document 2).